Tape transducing apparatus, and more particularly magnetic tape apparatus suitable for recording or reproduction of digitally coded television signals preferably used tape wound on winding reels located in cassettes. Different lengths of programs can be stored on reels, and in sets having different dimensions. The widths dimension of the tape is standardized, and thus the thickness of the cassette will be the same even though the length of the tape wound on reels may differ. Long tapes require large reels; shorter tapes can be wound on smaller reels. Thus, cassettes of different dimensions can be used and it has been proposed to provide three standard cassette sizes, small (S), medium (M) and large (L). In one proposal, the plan dimensions of the cassettes would be for the S-cassette, about 172.times.109 mm, for the M-cassette, 254.times.150 mm, and for the L-cassette, 360.times.206 mm. All three types of cassettes are formed with guide grooves at the bottom side of the cassette housing. The guide grooves have similar cross-sectional dimension, but are of different lengths.
A cassette transducing system should be capable of accepting any of the differently dimensioned cassettes of the set of cassettes. Loading should be simple and, preferably automatic, by a cassette loading transport system which pulls the respective cassettes into the well of the housing provided for the reception of the cassette and retaining the transducing apparatus. The widths of the cassette well will, of course, be of sufficient size to accept the largest one of the cassettes of the set. When the user wishes to insert the largest one of the cassettes, it can readily be fitted into the cassette reception opening and properly place the cassette in the cassette receiving well. If, however, a smaller cassette, for example a M-, or S-cassette is to be inserted, the user must be guided regarding proper positioning so that the cassette will be introduced centrally within the opening, that is, along a longitudinal line of symmetry--with respect to the insertion opening--so that the tape will be properly positioned with respect to tape handling and/or transducing apparatus within the housing. The user, thus, must be guided for proper placement, which can be located with some practice. The guide groove for all three types of cassettes is enlarged at the entrance in order to facilitate the centering of the cassette. Frequently, however, and particularly if change of cassette has to be carried out rapidly, under time pressure, in the dark, or otherwise without being able to pay close attention to proper insertion, misalignment of the cassette with the transducing apparatus may occur.
The cassettes may be used in studio application and/or combination with editing or reproduction of news reports, so that leisurely and careful insertion of cassettes into the transducer apparatus is not always possible.
U.S. Pat. No. 4,329,313 describes a tape cassette loading apparatus which, however, is suitable only for a single size of cassettes. Published European application EP No. 0 133 822 describes a drive arrangement for magnetic tape cassettes in which the spacing of the axes of rotation of the respective tape reels differs, so that magnetic tape cassettes of different sizes can be handled by the apparatus. This apparatus, however, requires careful placement of the respective cassettes so that they will be located in centered position, and no provision has been made to facilitate or guide the insertion of cassettes which are smaller than the largest cassette opening in precisely centered appropriate position.